In order to make aircraft passengers comfortable, and in order to transport them between an airport terminal building and an aircraft in such a way that they are protected from weather and other environmental influences, passenger boarding bridges are used which can be telescopically extended and the height of which is adjustable. For instance, an apron drive bridge in present day use includes a plurality of adjustable modules, including: a rotunda, a telescopic tunnel, a bubble section, a cab, and elevating columns with wheel carriage. Other common types of passenger boarding bridges include radial drive bridges and over-the-wing (OTW) bridges. These types of passenger boarding bridges are adjustable, for instance to compensate for different sized aircraft and to compensate for imprecise parking of aircraft at an airport terminal.
Nowadays, passenger boarding bridges are used increasingly to service aircraft doorways that pose particular challenges, which raises new concerns regarding passenger safety, the risk of causing damage to the aircraft and the effects of bridge failure. The design of very large aircraft, such as for instance the Airbus A380, requires elevation of the aircraft-engaging end of the passenger boarding bridge to a height of about 26.6 feet above the apron in order to service an upper deck doorway of the aircraft. At this height above the ground, passenger safety is compromised under conditions that render the passenger boarding bridge unstable, such as for instance windy conditions. Furthermore, the U1 doorway is located elevationally above the A380 left wing, thereby requiring the passenger boarding bridge to be extended over the wing of the aircraft during the alignment operation. Clearly, passenger boarding bridge stability is of great importance.
One solution is to incorporate stabilizing jacks adjacent the ends of the wheel carriage and outside of the drive wheels. When deployed, the jacks provide a wider support base compared to a standard wheel carriage, and assist in stabilizing the tunnel section high above the ground and/or over the wing of the aircraft. Unfortunately, a human bridge operator is prone to forgetting to deploy the stabilizing jacks, or may even deliberately choose not to deploy the stabilizing jacks under conditions that are judged to be safe. For instance, calm wind conditions may prompt a human operator to forego deploying the stabilizing jacks so as to save time if the passenger boarding bridge requires additional minor adjustments, or if the turn-around time of the aircraft is very short. Unfortunately, conditions may change rapidly or the human operator may misjudge operating conditions, thereby subjecting unnecessarily the passengers and the aircraft to risk.
It would be advantageous to provide a system and method that overcomes at least some of the above-mentioned limitations.